/**
 * Software License, Version 1.0
 * 
 * Copyright 2003 The Trustees of Indiana University.  All rights reserved.
 * 
 *
 *Redistribution and use in source and binary forms, with or without 
 *modification, are permitted provided that the following conditions are met:
 *
 *1) All redistributions of source code must retain the above copyright notice,
 * the list of authors in the original source code, this list of conditions and
 * the disclaimer listed in this license;
 *2) All redistributions in binary form must reproduce the above copyright 
 * notice, this list of conditions and the disclaimer listed in this license in
 * the documentation and/or other materials provided with the distribution;
 *3) Any documentation included with all redistributions must include the 
 * following acknowledgement:
 *
 *"This product includes software developed by the Community Grids Lab. For 
 * further information contact the Community Grids Lab at 
 * http://communitygrids.iu.edu/."
 *
 * Alternatively, this acknowledgement may appear in the software itself, and 
 * wherever such third-party acknowledgments normally appear.
 * 
 *4) The name Indiana University or Community Grids Lab or NaradaBrokering, 
 * shall not be used to endorse or promote products derived from this software 
 * without prior written permission from Indiana University.  For written 
 * permission, please contact the Advanced Research and Technology Institute 
 * ("ARTI") at 351 West 10th Street, Indianapolis, Indiana 46202.
 *5) Products derived from this software may not be called NaradaBrokering, 
 * nor may Indiana University or Community Grids Lab or NaradaBrokering appear
 * in their name, without prior written permission of ARTI.
 * 
 *
 * Indiana University provides no reassurances that the source code provided 
 * does not infringe the patent or any other intellectual property rights of 
 * any other entity.  Indiana University disclaims any liability to any 
 * recipient for claims brought by any other entity based on infringement of 
 * intellectual property rights or otherwise.  
 *
 *LICENSEE UNDERSTANDS THAT SOFTWARE IS PROVIDED "AS IS" FOR WHICH NO 
 *WARRANTIES AS TO CAPABILITIES OR ACCURACY ARE MADE. INDIANA UNIVERSITY GIVES
 *NO WARRANTIES AND MAKES NO REPRESENTATION THAT SOFTWARE IS FREE OF 
 *INFRINGEMENT OF THIRD PARTY PATENT, COPYRIGHT, OR OTHER PROPRIETARY RIGHTS. 
 *INDIANA UNIVERSITY MAKES NO WARRANTIES THAT SOFTWARE IS FREE FROM "BUGS", 
 *"VIRUSES", "TROJAN HORSES", "TRAP DOORS", "WORMS", OR OTHER HARMFUL CODE.  
 *LICENSEE ASSUMES THE ENTIRE RISK AS TO THE PERFORMANCE OF SOFTWARE AND/OR 
 *ASSOCIATED MATERIALS, AND TO THE PERFORMANCE AND VALIDITY OF INFORMATION 
 *GENERATED USING SOFTWARE.
 */
/**
 * Software License, Version 1.0
 * 
 * Copyright 2003 The Trustees of Indiana University.  All rights reserved.
 * 
 *
 *Redistribution and use in source and binary forms, with or without 
 *modification, are permitted provided that the following conditions are met:
 *
 *1) All redistributions of source code must retain the above copyright notice,
 * the list of authors in the original source code, this list of conditions and
 * the disclaimer listed in this license;
 *2) All redistributions in binary form must reproduce the above copyright 
 * notice, this list of conditions and the disclaimer listed in this license in
 * the documentation and/or other materials provided with the distribution;
 *3) Any documentation included with all redistributions must include the 
 * following acknowledgement:
 *
 *"This product includes software developed by the Community Grid Labs. For 
 * further information contact the Community Grid Labs at 
 * http://communitygrids.iu.edu/."
 *
 * Alternatively, this acknowledgement may appear in the software itself, and 
 * wherever such third-party acknowledgments normally appear.
 * 
 *4) The name Indiana University or Community Grid Labs or NaradaBrokering, 
 * shall not be used to endorse or promote products derived from this software 
 * without prior written permission from Indiana University.  For written 
 * permission, please contact the Advanced Research and Technology Institute 
 * ("ARTI") at 351 West 10th Street, Indianapolis, Indiana 46202.
 *5) Products derived from this software may not be called NaradaBrokering, 
 * nor may Indiana University or Community Grid Labs or NaradaBrokering appear
 * in their name, without prior written permission of ARTI.
 * 
 *
 * Indiana University provides no reassurances that the source code provided 
 * does not infringe the patent or any other intellectual property rights of 
 * any other entity.  Indiana University disclaims any liability to any 
 * recipient for claims brought by any other entity based on infringement of 
 * intellectual property rights or otherwise.  
 *
 *LICENSEE UNDERSTANDS THAT SOFTWARE IS PROVIDED "AS IS" FOR WHICH NO 
 *WARRANTIES AS TO CAPABILITIES OR ACCURACY ARE MADE. INDIANA UNIVERSITY GIVES
 *NO WARRANTIES AND MAKES NO REPRESENTATION THAT SOFTWARE IS FREE OF 
 *INFRINGEMENT OF THIRD PARTY PATENT, COPYRIGHT, OR OTHER PROPRIETARY RIGHTS. 
 *INDIANA UNIVERSITY MAKES NO WARRANTIES THAT SOFTWARE IS FREE FROM "BUGS", 
 *"VIRUSES", "TROJAN HORSES", "TRAP DOORS", "WORMS", OR OTHER HARMFUL CODE.  
 *LICENSEE ASSUMES THE ENTIRE RISK AS TO THE PERFORMANCE OF SOFTWARE AND/OR 
 *ASSOCIATED MATERIALS, AND TO THE PERFORMANCE AND VALIDITY OF INFORMATION 
 *GENERATED USING SOFTWARE.
 */
package cgl.narada.topology.viewer;

/**
   This class implements some of the utilies commonly used during performance
   measurements on links and by other programs.

   @author Shrideep Pallickara
   $Date$
   $Revision$
*/

public class StatUtils {

  private static long[] 
  getMaxValues(long [] values, int numOfValues, int maxReject) {
    long[] maxValues = new long[maxReject];
    for (int i=0; i < maxReject; i++) {
      maxValues[i] = (long)0;
    }
    for (int i=0; i < numOfValues; i++) {
      for (int j=0; j < maxReject; j++) {
	if (values[i] >= maxValues[maxReject-1-j]) {
	  for (int k=0; k< maxReject-1-j; k++) {
	    maxValues[k] = maxValues[k+1];
	  }/*(k)*/
	  maxValues[maxReject-1-j] = values[i];
	  break;
	}/** if statement - for reorganizing the max array */
      }/*(j)*/
    }/*(i)*/

    return maxValues;
  } 

  public static double 
  computeMean(long [] values, int numOfValues, int maxReject) {
    long[] maxValues = getMaxValues(values, numOfValues, maxReject);
    
    long addValues=0;
    double meanValue=0;
    
    for(int i=0; i <numOfValues; i++) {
      addValues+= values[i];
    }
    for (int i=0; i < maxReject; i++) {
      addValues-= maxValues[i];
    }
    
    meanValue =
      (double)addValues/(double)(numOfValues-maxReject);
    return meanValue;
  } /* end compute mean value*/


  public static double 
  computeStandardDeviation(long [] values, int numOfValues, int maxReject) {
    double meanValue = computeMean(values, numOfValues, maxReject);
    long[] maxValues = getMaxValues(values, numOfValues, maxReject);

    double squaredDifferenceOfMeanAndSample = 0;
    for (int i = 0; i< numOfValues; i++) {
      squaredDifferenceOfMeanAndSample +=
	(Math.pow((values[i]- meanValue),2) );
    }

    for (int i = 0; i < maxReject; i++) {
      squaredDifferenceOfMeanAndSample -=
	(Math.pow((maxValues[i]- meanValue),2) );
    }
    
    double variance =
      squaredDifferenceOfMeanAndSample/(numOfValues-maxReject-1);
    double stdDeviation = Math.sqrt(variance);
    return stdDeviation;
  } /* end compute standard deviation */


  public static double computeJitter(double jitter, double delayD, 
				     double delayDplusOne) {
    
    jitter +=  ( Math.abs( (double)(delayD - delayDplusOne) ) - jitter )/16;
    return jitter;
  }
  
  
}


